The invention relates to a method for manufacturing components consisting of one piece which appear in a weaving machine, comprising one or more first and second parts, said parts being manufactured in separate first and second parts and being joined to form one piece by means of processes which practically do not change the cross-section of said parts.
Up to the present, in weaving machines, one has to deal with manufacturing long components having a small cross-section, the manufacturing process selected being determined by the requirements which may be imposed on a local part of the components, but where the method of manufacturing is applied to the entire component. By long components are meant components having a total length situated between about 0.4 and 2 meters, the local parts determining the method of manufacturing for the total component being shorter than 0.3 meters.
Moreover, specific tribological, mechanical and/or magnetic properties are required for these local parts. By tribological properties are meant, for instance, being free of burrs, pure, polished, etc. Furthermore, these local parts may be subjected to certain specific requirements as to their shape, for instance having recesses, deflections, local broadenings and others and/or combinations of these features.
The disadvantage is, that most of the time, the method for manufacturing these local parts is expensive and/or labor-intensive. Because the method of production required has to be applied for the entire part, and the tribological, mechanical and/or magnetic properties required are possibly required for the parts which are not essential for the method of production, the costs for production of such long parts are very strongly increased, and obviously additional costs and labor are required.
More particularly, the invention relates to, for instance, heddles, lancets, hooks, etc., where the properties, method of production and/or other provisions required for a local part of these components are essential for the entire component, because of which manufacturing such components is an expensive matter.
In JP 60119245 a method is described, for instance, for manufacturing a heddle, which is used in a weaving machine, comprising a narrow centerpiece, which has an opening through which a yarn may be passed, and both extremities of which have an indentation or a hole to be connected to a heddle rod. The narrow centerpiece being made independently of the rest from sheet metal and attached to it. The sheet metal may consist of rolled leaves having rounded sides. Holes and/or indentations have been punched in them and then they are welded by means of a laser or electron beam. Such a method solves the problem that one stage of the process, for instance, a polishing or grinding process, to give the heddle its final shape, may be reduced or eliminated.
The drawback of such a heddle is that the center piece and the outer parts are made of the same material, whereas the center and outer parts have different functions, and the material used for the center part is less optimal for the outer parts and inversely, or that a material is selected which will be a compromise between the requirements for both parts.
In BE 571 667 a harness loop is described for weaving machines, more particularly at the extremity of hooks for a harness free of riders. In addition to openings for the guide rails and for the warp yarns, these harness loops have at least one discontinuity or opening at each extremity in the direction of the plane formed by the harness loops lined up, by means of which they are laced up to an independent lining up instrument. Thus, for instance, the harness loop at its extremity has a hook, which is hung onto a U-shaped channel corresponding to a guide rail, which is attached, for instance, to a supporting rod of the weaving machine or is part of it. The hook is connected to the spindle of the harness loop by means of a welding or brazing process.
A disadvantage of such a harness loop is that the parts connected to one another are each machined at their extremity to such a form that both parts are fitting together in a manner that they may be removed from one another in the longitudinal direction. This fit is secured by a weld. Machining these parts is time-consuming and expensive and the welded part has bulges caused by the weld.